Liam stone



(Specimens.)

D. MACDONALD.

SIGN PLATE.

No. 396,704. Patented Jan'. 22, 1889.

QLSA..

N. PETERS. nowmmmpher. wumngw", D. r.

NITED Sterns PATENT OFFICE.

DAVID MACDONALD, OF TORONTO, ONTARIO, CANADA, ASSIGNOR TO IIL- IIIAM STONE, OF SAME PLACE.

SIGNIFLATE.

SPECIFICATION forming part of Letters Patent No. 396,704, dated January 22, 1889.

Application filed April 1l, 1888. Serial No. 270,261. (Specimens.)

To all whom it 71mg/ concern.-

Be it known that I, DAVID MACDONALD, of Toronto, in the Province of Ontario and Dominion of Canada, have invented certain new and useful Improvements in Sign-Plates, of which the following is a specification.

rllhis invention relates to an improved signplate in which a metal foundation plate or backing is combined by an intermediate layer of cement with a face layer of paper, said paper being sized and varnished, said signplate being,` specially adapted for lithographie work, such as showcards, znlvertising-pictures, and the like; and the invention consists of a sign-plate composed of a metal foundation plate or backingr having` a porous or roughened surface, an intermediate layer of cement, and a face layer of sized and varnished paper united with'said foundationplate by pressure.

In the acco1n],)anying' drawings, Figure l represents a front View of my improved signplate with the parts of the ditlerent layers successively lnoken away; and Fig. 2 is a vertical transverse section on line r a', Fig. l.

Similar letters ot' reference indicate correspondin parts.

In the drawings, a represents a metal foundation plate or backing, the surface of which is made porous by treating it with a suitable acid. On this porous surface a layer, 11,0f Cement, consisting, preferably, of a mixture of iine varnish-such as used by coach-buildM ers-and zinc-white, is uniformly spread, and then a layer, c, of paper printed in suitable colors placed thereon and embodied therewith by strong pressure in a suitable press. To protect the surface of the face layer, it is sized, and nally coated with varnish. By the pressure exerted on the dierent layers 4o the paper is thoroughly amalgamat-ed by the intermediate layer of cement with the porous or prepared surface of the plate, so that it is impossible to peel it oif. The sizing and varnishing protects the surface, so that it can 45 be handled, shipped, and exposed to moisture in the same manner as the met-al sign-plates on which the pictures Vhave been painted or otherwise fixed.

Having' thus described my invention, I claim 5o as new and desire to secure by Letters Patentl. A sign-plate composed of a metal foundation plate or backing' having a porous or roughened surface, an intermediate layer of cement, and a face layer of paper united with 55 the foundationplate by pressure, substantially as set forth.

2. A sign-plate composed of a metal foundation plate or backing having a porous or roughened surface, an intermediate layer of 6o cement, and a face layer of sized and Varnished paper united with the foundation-plate by pressure, substantially as set forth.

In testimony that I elaim the foregoing as my invention I have signed my name in pres- 6 5 ence of two subscribing` witnesses.

DAVID MACDONALD.

Witnesses:

ANDREW ALLAN, W. A. MITCHELL. 

